[INFO] fetching crate flow_macro 0.42.0...
[INFO] testing flow_macro-0.42.0 against 1.60.0 for beta-1.61-1
[INFO] extracting crate flow_macro 0.42.0 into /workspace/builds/worker-23/source
[INFO] validating manifest of crates.io crate flow_macro 0.42.0 on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate flow_macro 0.42.0
[INFO] finished tweaking crates.io crate flow_macro 0.42.0
[INFO] tweaked toml for crates.io crate flow_macro 0.42.0 written to /workspace/builds/worker-23/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded flowcore v0.42.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2c3049a8b55fc2c3a4742c8bf0b5774e9dc1a07a1c87e8b67f3b18edbef491a9
[INFO] running `Command { std: "docker" "start" "-a" "2c3049a8b55fc2c3a4742c8bf0b5774e9dc1a07a1c87e8b67f3b18edbef491a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2c3049a8b55fc2c3a4742c8bf0b5774e9dc1a07a1c87e8b67f3b18edbef491a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2c3049a8b55fc2c3a4742c8bf0b5774e9dc1a07a1c87e8b67f3b18edbef491a9", kill_on_drop: false }`
[INFO] [stdout] 2c3049a8b55fc2c3a4742c8bf0b5774e9dc1a07a1c87e8b67f3b18edbef491a9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 61b861918ebaf9b648fb96c71d1546e60153957e6648df1805cbc25cd309f462
[INFO] running `Command { std: "docker" "start" "-a" "61b861918ebaf9b648fb96c71d1546e60153957e6648df1805cbc25cd309f462", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling cc v1.0.73
[INFO] [stderr]    Compiling proc-macro2 v1.0.37
[INFO] [stderr]    Compiling pkg-config v0.3.25
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling syn v1.0.91
[INFO] [stderr]    Compiling libc v0.2.123
[INFO] [stderr]    Compiling serde_derive v1.0.136
[INFO] [stderr]    Compiling serde v1.0.136
[INFO] [stderr]    Compiling tinyvec_macros v0.1.0
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling matches v0.1.9
[INFO] [stderr]    Compiling adler v1.0.2
[INFO] [stderr]    Compiling percent-encoding v2.1.0
[INFO] [stderr]    Compiling curl v0.4.43
[INFO] [stderr]    Compiling unicode-bidi v0.3.7
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling gimli v0.26.1
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling rustc-demangle v0.1.21
[INFO] [stderr]    Compiling serde_json v1.0.79
[INFO] [stderr]    Compiling hashbrown v0.11.2
[INFO] [stderr]    Compiling ryu v1.0.9
[INFO] [stderr]    Compiling log v0.4.16
[INFO] [stderr]    Compiling either v1.6.1
[INFO] [stderr]    Compiling openssl-probe v0.1.5
[INFO] [stderr]    Compiling linked-hash-map v0.5.4
[INFO] [stderr]    Compiling itoa v1.0.1
[INFO] [stderr]    Compiling bitflags v1.3.2
[INFO] [stderr]    Compiling form_urlencoded v1.0.1
[INFO] [stderr]    Compiling yaml-rust v0.4.5
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling indexmap v1.8.1
[INFO] [stderr]    Compiling tinyvec v1.5.1
[INFO] [stderr]    Compiling object v0.27.1
[INFO] [stderr]    Compiling openssl-sys v0.9.72
[INFO] [stderr]    Compiling libz-sys v1.1.5
[INFO] [stderr]    Compiling curl-sys v0.4.53+curl-7.82.0
[INFO] [stderr]    Compiling backtrace v0.3.64
[INFO] [stderr]    Compiling error-chain v0.12.4
[INFO] [stderr]    Compiling socket2 v0.4.4
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling addr2line v0.17.0
[INFO] [stderr]    Compiling unicode-normalization v0.1.19
[INFO] [stderr]    Compiling idna v0.2.3
[INFO] [stderr]    Compiling shrinkwraprs v0.3.0
[INFO] [stderr]    Compiling url v2.2.2
[INFO] [stderr]    Compiling serde_yaml v0.8.23
[INFO] [stderr]    Compiling toml v0.5.8
[INFO] [stderr]    Compiling simpath v2.3.0
[INFO] [stderr]    Compiling flowcore v0.42.0
[INFO] [stderr]    Compiling flow_macro v0.42.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(proc_macro_span)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `flow_macro` due to 2 previous errors
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "61b861918ebaf9b648fb96c71d1546e60153957e6648df1805cbc25cd309f462", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "61b861918ebaf9b648fb96c71d1546e60153957e6648df1805cbc25cd309f462", kill_on_drop: false }`
[INFO] [stdout] 61b861918ebaf9b648fb96c71d1546e60153957e6648df1805cbc25cd309f462